Large artery stiffness and carotid intima-media thickness in relation to markers of calcium and bone mineral metabolism in African women older than 46 years

Association of bone turnover biomarkers with severe intracranial and extracranial artery stenosis in type 2 diabetes mellitus patients

BACKGROUND

Intracranial and extracranial artery stenosis is associated with cerebral infarction. Vascular calcification and atherosclerosis are the main causes of stenosis and major risk factors for cardiovascular and cerebrovascular events in patients with type 2 diabetes mellitus (T2DM). Bone turnover biomarkers (BTMs) are associated with vascular calcification, atherosclerosis, glucose, and lipid metabolism.

AIM

To investigate the association of circulating BTM levels with severe intracranial and extracranial artery stenosis in patients with T2DM.

METHODS

For this cross-sectional study including 257 T2DM patients, levels of the BTMs serum osteocalcin (OC), C-terminal cross-linked telopeptide of type I collagen (CTX), and procollagen type I N-peptide were measured by electrical chemiluminescent immunoassay, and artery stenosis was assessed by color Doppler and transcranial Doppler. Patients were grouped according to the existence and location (intracranial vs. extracranial) of artery stenosis. Correlations between BTM levels, previous stroke, stenosis location, and glucose and lipid metabolism were analyzed.

RESULTS

T2DM patients with severe artery stenosis had a higher frequency of previous stroke and levels of all three tested BTMs (all P < 0.05) than patients without. Some differences in OC and CTX levels were observed according to the location of artery stenosis. Significant associations were also observed between BTM levels and some glucose and lipid homeostasis parameters. On multivariate logistic regression analysis, all BTMs were significant predictors of artery stenosis in T2DM patients with and without adjustment for confounding factors (all P < 0.001), and receiver operating characteristic curve analysis demonstrated the ability of BTM levels to predict artery stenosis in T2DM patients.

CONCLUSION

BTM levels were found to be independent risk factors for severe intracranial and extracranial artery stenosis and were differentially associated with glucose and lipid metabolism in patients with T2DM. Therefore, BTMs may be promising biomarkers and potential therapeutic targets for artery stenosis.

Association between obesity and risk of fracture, bone mineral density and bone quality in adults: A systematic review and meta-analysis

BACKGROUND

The association between obesity and fracture risk may be skeletal site- and sex-specific but results among studies are inconsistent. Whilst several studies reported higher bone mineral density (BMD) in patients with obesity, altered bone quality could be a major determinant of bone fragility in this population.

OBJECTIVES

This systematic review and meta-analysis aimed to compare, in men, premenopausal women and postmenopausal women with obesity vs. individuals without obesity: 1) the incidence of fractures overall and by site; 2) BMD; and 3) bone quality parameters (circulating bone turnover markers and bone microarchitecture and strength by advanced imaging techniques).

DATA SOURCES

PubMed (MEDLINE), EMBASE, Cochrane Library and Web of Science were searched from inception of databases until the 13th of January 2021.

DATA SYNTHESIS

Each outcome was stratified by sex and menopausal status in women. The meta-analysis was performed using a random-effect model with inverse-variance method. The risks of hip and wrist fracture were reduced by 25% (n = 8: RR = 0.75, 95% CI: 0.62, 0.91, P = 0.003, I2 = 95%) and 15% (n = 2 studies: RR = 0.85, 95% CI: 0.81, 0.88), respectively, while ankle fracture risk was increased by 60% (n = 2 studies: RR = 1.60, 95% CI: 1.52, 1.68) in postmenopausal women with obesity compared with those without obesity. In men with obesity, hip fracture risk was decreased by 41% (n = 5 studies: RR = 0.59, 95% CI: 0.44, 0.79). Obesity was associated with increased BMD, better bone microarchitecture and strength, and generally lower or unchanged circulating bone resorption, formation and osteocyte markers. However, heterogeneity among studies was high for most outcomes, and overall quality of evidence was very low to low for all outcomes.

CONCLUSIONS

This meta-analysis highlights areas for future research including the need for site-specific fracture studies, especially in men and premenopausal women, and studies comparing bone microarchitecture between individuals with and without obesity.

SYSTEMATIC REVIEW REGISTRATION NUMBER

CRD42020159189.

CRP Genotypes Predict Increased Risk to Co-Present with Low Vitamin D and Elevated CRP in a Group of Healthy Black South African Women

Low 25-hydroxyvitamin D (25(OH)D) and elevated C-reactive protein (CRP) concentrations are independently associated with adverse health outcomes, including cardiovascular disease (CVD). Although an inverse association between these factors has been described, the underlying mechanisms remain unknown. We postulate that environment-gene interactions, through which 25(OH)D interacts with single nucleotide polymorphisms (SNPs) within the CRP gene, modulate CRP; that certain CRP genotypes predispose individuals to a co-phenotype of low 25(OH)D and elevated CRP concentrations; and that this co-phenotype is associated with higher CVD risk. Twelve CRP SNPs were genotyped, and both 25(OH)D and CRP were quantified, in 505 black South African women. Alarmingly, 66% and 60% of the women presented with deficient/insufficient 25(OH)D and elevated CRP concentrations, respectively. CRP concentrations were higher in individuals with lower 25(OH)D concentrations. However, no 25(OH)D-CRP genotype interactions were evident. Several genotypes were associated with an altered risk of presenting with the co-phenotype, indicating a genetic predisposition. Women presenting with this co-phenotype had higher blood pressure and increased anthropometric measures, which may predispose them to develop CVD. We recommend increasing vitamin D fortification and supplementation efforts to reduce inflammation among black women with vitamin D deficiency, thereby possibly curbing diseases contingent on the co-phenotype described here.

Sodium and potassium intake in South Africa: an evaluation of 24-hour urine collections in a white, black, and Indian population

Limited number of studies on salt intake has been conducted in the South Africa. The present study established the sodium and potassium excretion (24-hour urine collection) of three different South African populations. In total, 692 successful 24-hour urine collections were analyzed for sodium, potassium, and iodine levels. The median sodium and potassium excretion was 122.9 and 33.5 mmol/d, respectively, and the median salt intake was 7.2 g/d. The majority (92.8%) of the population did not meet the recommended potassium intake/d, and 65.6% consumed more than 6 g of salt/d. Potassium excretion showed a linear relationship with salt intake (P-trend ≤ .001). The median sodium-to-potassium ratio was 3.5. These findings support the South African government's sodium reduction legislation, as well as global initiatives. More consideration should be given to promoting the intake of potassium-rich foods, as this may have a greater public health impact than focusing only on dietary sodium reduction.